“Sometimes things are unfair and don’t go as planned,” Sigmundsdottir wrote in a post on Instagram.

“It is one of the hardest things I have ever had to do in my life but I have decided to withdraw from the competition due to a stress fracture injury on my rib.

“This decision is made after a consultation with my coach and doctors. There was only one decision to be made, and as much as I hate the fact that I am not going to finish this competition I know that this is the only right way to proceed.”

“Afterwards the pain got so much worse of course. I started Friday, still in denial, and after the ‘Clean and jerk ladder’ pain killers had become my best friend.

“I decided to keep on pushing today regardless of all the alarm bells but once I started warming up for events nine and 10 the pain had become so bad that I could not bend over to do a snatch or complete a muscle up on the bar.”

Sigmundsdottir promised to provide a more detailed explanation of her injury when she knows more about it.

“One thing is for sure, I’ll be back!” she wrote at the end of the post on Instagram. She had written another post earlier on Saturday saying “I have a really good feeling about what is in front of us and I’m ready to push with everything I’ve got”.

Her withdrawal follows that of Michele Fumagalli on the opening day, with the American fracturing her wrist after falling off her bike on the last turn of the final lap during the women’s Crit.

Emily Bridgers then ended her CrossFit Games career by retiring early after sustaining an ankle injury during the Battleground obstacle course on Friday, in what was her fifth and final Games.

Meanwhile, it was revealed Justine Beath was disqualified from the 2018 CrossFit Games after failing to meet the minimum work requirement on the obstacle course during the Battleground event on Friday.

“Well that’s a wrap for me,” Beath wrote on Instagram. “To fail publicly then be cut on the biggest stage there is in this sport on the SECOND day of competition after training as hard as I could, being in the best shape physically and mentally, is not something I had ever thought about.